Michael Scott - kwa zaka 34 как профессор Computer Science в Рочестерском университетe, а в родном универститете Wisconsin–Madison был деканом в течение пяти лет. Он занимается исследованиям в области параллельного и распределённого программирования и дизайна языков и обучает этому студентов.

Dziko lapansi limamudziwa Michael kuchokera m'mabuku "Programming Language Pragmatics", nanga ntchito "Ma algorithms olumikizirana scalable pa ma share-memory multiprocessors" adalandira Mphotho ya Dijkstra ngati imodzi mwazambiri zodziwika bwino pamakompyuta ogawa. Mutha kumudziwanso ngati mlembi wa algorithm yomweyo Michael-Scott.

Pamodzi ndi Doug Lee, adapanga ma algorithms osatsekereza ndi mizere yolumikizana yomwe imayendetsa malaibulale a Java. Kukhazikitsa "dual data structures" mu JavaSE 6 idachita bwino nthawi 10 ThreadPoolExecutor.

Zamkatimu:

• Ntchito yoyambirira, University of Rochester. Project Charlotte, chinenero cha Lynx;
• IEEE Scalable Coherent Interface, kutseka kwa MCS;
• Kupulumuka m'dziko losintha nthawi zonse;
• Kodi ophunzira akukhala opusa? Zochitika zapadziko lonse lapansi, kugwirizanitsa mayiko;
• Kuchita bwino ndi ophunzira;
• Momwe mungapitirizire kukonzekera maphunziro atsopano ndi mabuku;
• Mgwirizano pakati pa bizinesi ndi maphunziro;
• Kuchita bwino kwa malingaliro. MCS, MS, CLH, JSR 166, kugwira ntchito ndi Doug Lee ndi zina;
• Transaction kukumbukira;
• Zomangamanga zatsopano. Kupambana kwa kukumbukira kwamalonda kuli pafupi;
• Kukumbukira kosasinthika, Optane DIMM, zida zothamanga kwambiri;
• Chotsatira chachikulu chotsatira. Mitundu iwiri ya data. Hydra.

Interview imachitidwa ndi:

Vitaly Aksenov - pano ndi postdoc ku IST Austria komanso membala wa dipatimenti ya Computer Technologies ku ITMO University. Imachita kafukufuku pankhani yamalingaliro ndi machitidwe amipikisano yama data. Asanagwire ntchito ku IST, adalandira PhD yake kuchokera ku yunivesite ya Paris Diderot ndi yunivesite ya ITMO moyang'aniridwa ndi Pulofesa Peter Kuznetsov.

Alexey Fedorov - Wopanga ku JUG Ru Group, kampani yaku Russia yomwe imakonza misonkhano ya otukula. Alexey adatenga nawo gawo pokonzekera misonkhano yopitilira 50, ndipo kuyambiranso kwake kumaphatikizapo chilichonse kuchokera paudindo wa injiniya wachitukuko ku Oracle (JCK, Java Platform Group) mpaka kukhala wopanga ku Odnoklassniki.

Vladimir Sitnikov -Injiniya ku Netcracker. Zaka khumi zogwira ntchito pakuchita komanso kuwopsa kwa NetCracker OS, mapulogalamu omwe amagwiritsidwa ntchito ndi oyendetsa ma telecom kuti azitha kuyendetsa makina ndi zida zogwirira ntchito. Ndimakonda zochitika za Java ndi Oracle Database. Wolemba zakusintha kopitilira khumi ndi awiri mu woyendetsa wovomerezeka wa PostgreSQL JDBC.

Ntchito yoyambirira, University of Rochester. Ntchito ya Charlotte, chilankhulo cha Lynx.

Алексей: Poyamba, ndimafuna ndikuuzeni kuti ku Russia tonse timakonda Computer Science, Data Science ndi ma algorithms. Ndi zotukwana ndithu. Tawerenga zonse Buku la Cormen, Leiserson ndi Rivest. Chifukwa chake, msonkhano womwe ukubwera, sukulu komanso kuyankhulana kumeneku payenera kukhala kotchuka kwambiri. Tinalandira mafunso ambiri pa zokambiranazi kuchokera kwa ophunzira, olemba mapulogalamu, ndi anthu ammudzi, choncho ndife oyamikira kwambiri mwayi umenewu. Kodi Computer Science imapeza chikondi chomwecho ku US?

Michael: Munda wathu ndi wosiyanasiyana, uli ndi mayendedwe ambiri, ndipo umakhudza anthu m'njira zosiyanasiyana kotero kuti zimandivuta kukupatsani yankho lotsimikizika. Koma zoona zake n’zakuti pazaka 30 zapitazi zasintha kwambiri mabizinesi, mafakitale, zaluso komanso anthu ambiri.

Vitali: Tiyeni tiyambe ndi chinthu chakutali. M'mayunivesite ambiri pali china chake monga ukatswiri m'dera linalake. Kwa Carnegie Mellon University iyi ndi computing yofananira, ya MIT ndi cryptography, maroboti ndi ma multithreading. Kodi pali ukatswiri wotere ku Yunivesite ya Rochester?

Michael: Kunena zowona, ndinganene kuti CMU ndi MIT amakhazikika m'malo onse. Dipatimenti yathu nthawi zonse yakhala ikuyang'ana kwambiri zanzeru zopangira. Theka la anthu omwe amagwira ntchito kwa ife akugwira nawo ntchito ya AI kapena makompyuta a anthu - gawo ili ndilokwera kuposa m'madipatimenti ena, ndipo zakhala choncho. Koma pamene ndinali ku yunivesite, ndinalibe maphunziro a AI, ndipo sindinagwirepo ntchito imeneyi. Chifukwa chake dipatimenti yanga imakhazikika pavuto lomwe ndilibe chochita nalo. Chitonthozo ndi chakuti vuto lachiwiri lofunika kwambiri la dipatimenti yathu ndilofanana ndi mapulogalamu amitundu yambiri, ndiko kuti, luso langa.

Vitali: Munayamba kugwira ntchito mu Computer Science pamene gawo la mapulogalamu amitundu yambiri likungoyamba kumene. Mndandanda wa zolemba zanu ukuwonetsa kuti ntchito zanu zoyamba zidathana ndi zovuta zingapo: kasamalidwe ka kukumbukira mumitundu yambiri, makina amafayilo, makina ogwiritsira ntchito. N'chifukwa chiyani kusinthasintha koteroko? Kodi mwakhala mukuyesera kupeza malo anu mu gulu la kafukufuku?

Michael: Monga wophunzira, ndinachita nawo Ntchito ya Charlotte ku yunivesite ya Wisconsin, kumene imodzi mwa machitidwe oyambirira omwe anagawira anapangidwa. Kumeneko ndinagwira ntchito limodzi ndi Rafael Finkel (Raphael Finkel) ndi Marvin Solomon (Marvin Solomon). Zolemba zanga zidaperekedwa pakupanga chilankhulo cha pulogalamu yamapulogalamu yamachitidwe ogawa - tsopano aliyense wayiwala za izi, ndipo zikomo Mulungu. Ndidapanga chilankhulo cha pulogalamu ya Lynx, chomwe chidapangidwa kuti chikhale chosavuta kupanga ma seva a makina ogwiritsira ntchito ogawidwa momasuka. Popeza panthaŵiyo ndinali wotanganidwa kwambiri ndi ma opaleshoni, ndinaganiza kuti ntchito yanga ikakhala yogwirizana nawo. Koma Rochester anali yunivesite yaing'ono kwambiri, ndipo chifukwa cha ichi, magulu osiyanasiyana kumeneko ankagwirizana kwambiri. Panalibe dazeni machitidwe ena opaleshoni anthu kumeneko kuti ndilankhule, kotero kulankhula wanga onse anali ndi anthu amene ankagwira ntchito zosiyanasiyana kotheratu. Ndinkasangalala nazo kwambiri, kukhala wochita zinthu zonse ndi mwayi waukulu kwa ine. Ngati tilankhula mwachindunji zamitundu yambiri yamitundu yambiri ndi ma aligorivimu olumikizana, ndiye kuti ndidayamba kuwagwirira ntchito mwangozi.

IEEE Scalable Coherent Interface, kutseka kwa MCS.

Vitali: Kodi mungandiuzeko pang'ono za izi?

Michael: Iyi ndi nkhani yoseketsa yomwe sinditopa kuuza aliyense. Izo zinachitika pa msonkhano ASPLOS ku Boston - uku kunali kumapeto kwa 80s kapena koyambirira kwa 90s. John Mellor-CrummeyJohn Mellor-Crummey), womaliza maphunziro athu. Ndinkamudziwa, koma tinali tisanafufuze pamodzi. Mary Vernon (Mary Vernon) ochokera ku Wisconsin adakamba nkhani yokhudza makina opangira ma multiprocessor omwe amapangidwa ku Wisconsin: Wisconsin Multicube. Multicube iyi inali ndi njira yolumikizirana pamlingo wa Hardware wotchedwa Q pa Sync Bit, ndipo pambuyo pake idatchedwanso Q pa Lock Bit chifukwa idamveka ngati tchizi ya Colby, yomwe inali pun. Ngati mukufuna njira zowerengera zambiri, mwina mukudziwa kuti Colby pamapeto pake idakhala injini yolumikizira muyeso wa IEEE Scalable Coherent Interface. Uwu unali njira yotsekera yomwe idapanga zolozera kuchokera ku cache kupita ku ina pamlingo wa hardware kuti chotchinga chilichonse chidziwe kuti ndi chandani. John ndi ine titamva za izi, tinayang'ana wina ndi mzake ndipo anati: chifukwa chiyani izi pa mlingo hardware? Kodi zinthu zomwezi sizingakwaniritsidwe poyerekezera ndi kusinthana? Tinatenga kabuku kamene kanali m’kalasimo n’kulembapo Kutsekeka kwa MCS, pamene Mariya anapitiriza lipoti lake. Pambuyo pake, tidakhazikitsa, kuyesa, lingalirolo lidakhala lopambana, ndipo tidasindikiza nkhaniyi. Panthawiyo, kwa ine, mutuwu unkawoneka ngati wosokoneza wosangalatsa, pambuyo pake ndinakonzekera kubwerera ku machitidwe opangira opaleshoni. Koma vuto linanso pamizere yomweyi lidabuka, ndipo pamapeto pake kulumikizana, kuwerengera zambiri, ndi mapangidwe a data zidakhala zanga zapadera. Monga mukuonera, zonsezi zinachitika mwangozi.

Vitali: Ndakhala ndikuzidziwa MCS blocking kwa nthawi yayitali, koma mpaka pano sindimadziwa kuti ndi ntchito yanu, komanso sindimamvetsetsa kuti ndi chidule cha mayina anu.

Kodi mungapulumuke bwanji m'dziko lomwe likusintha nthawi zonse?

Алексей: Ndili ndi funso pamutu wogwirizana nawo. Zaka 30 kapena 40 zapitazo panali ufulu wochuluka muzochita zosiyanasiyana. Ngati mukufuna kuyamba ntchito mu multithreading kapena kugawa machitidwe, ndinu olandiridwa, ngati mukufuna kulowa machitidwe opaleshoni, palibe vuto. M'dera lililonse munali mafunso ambiri otseguka ndi akatswiri ochepa. Katswiri wopapatiza tsopano atulukira: palibe akatswiri okha pa machitidwe opangira ntchito, pali akatswiri pa machitidwe a munthu aliyense. Ndizofanana ndi ma multithreading ndi makina ogawa. Koma vuto ndi loti moyo wathu siwotha; aliyense atha kuthera zaka makumi angapo kuti afufuze. Kodi tidzapulumuka bwanji m’dziko latsopanoli?

Michael: Sitili apadera pankhaniyi; zomwezi zidachitikanso m'malo ena. Ndinali ndi mwayi kuti ndinayamba kugwira ntchito mu Computer Science pamene munda unali mu "zaka zaunyamata". Maziko ena anali atayikidwa kale, koma zonse zinali zidakali zachibwana. Mwayi umenewu sumabwera nthawi zambiri. Ukatswiri wamagetsi wakhalapo kwa nthawi yayitali kwambiri, fizikisi ngakhale motalikirapo, masamu pafupifupi kuyambira chiyambi cha nthawi. Koma izi sizikutanthauza kuti palibenso amene akutulukira zinthu zosangalatsa mu masamu. Palinso mavuto ambiri otseguka, koma panthawi imodzimodziyo, zambiri ziyenera kuphunzitsidwa. Mukunena zowona kuti tsopano pali akatswiri ochulukirapo kuposa kale, koma izi zimangotanthauza kuti tili mumkhalidwe wofanana ndi mbali zina zambiri za zochita za anthu.

Алексей: Ndili ndi chidwi ndi mbali yothandiza kwambiri ya nkhaniyi pano. Ndili ndi mbiri ya masamu, ndipo pa maphunziro anga nthawi zambiri ndinkapita kumisonkhano ndikugwira ntchito zosiyanasiyana za sayansi. Ndinazindikira kuti palibe aliyense mwa omvetsera amene anamvetsetsa malipoti anga, ndipo mofananamo, malipoti a anthu ena anali omveka kwa iwo okha. Izi sizili choncho pamitu yapamwamba, koma mutangoyamba kufufuza chinachake, omvera sangathenso kukhala ndi inu. Kodi mumathana nazo bwanji?

Michael: Sizimakhala bwino nthawi zonse. Posachedwapa ndakonza lipoti lomwe ndidapita mozama muzambiri zaukadaulo. Pamene nkhaniyo inkapitirira, zinaonekeratu kuti omvera ambiri sankandimvetsa, choncho ndinafunika kuzolowerana ndi mmene zinthu zinalili panthawiyi. Makanema sanasinthidwe, kotero sizinali bwino - kotero, kunena zambiri, ndimayesetsa kusagwiritsa ntchito zithunzi. Ponseponse, upangiri wanga ndikuganizira omvera anu. Muyenera kudziwa yemwe mukulankhula naye, kuchuluka kwa chidziwitso chawo, ndi zomwe akuyenera kumva kuti ayamikire ntchito yanu.

Vitali: Kodi mungatipatseko lingaliro la zomwe phunziroli likunena?

Michael: Kunena zowona, ndikanakonda kuti ndisafutukule pamutuwu kuti anthu omwe akufunsidwa asadziwike. Mfundo ndi yakuti nthawi zambiri timakhala ozama kwambiri pa zovuta zomwe tikulimbana nazo, choncho zimakhala zovuta kuti tifotokoze kumayambiriro kwa nkhaniyo chifukwa chake vutolo ndi losangalatsa komanso lofunika komanso momwe limagwirizanirana ndi nkhani zomwe omvera akudziwa kale. Malinga ndi zomwe ndaona, ophunzira amavutika kwambiri kuphunzira luso limeneli. Ndipo ichi chinalinso chofooka cha lipoti langa laposachedwa. Lipoti lokonzedwa bwino liyenera, kuyambira pachiyambi penipeni, kupeza kulumikizana ndi omvera, kuwafotokozera chomwe vuto ndi chiyani komanso momwe likukhudzira mitu yomwe yadziwika kale. Momwe mawu oyambawa alili aukadaulo zimadalira omvera. Ngati ili ndi motley, ndiye kuti lipotilo likhoza kukhala lamitundu yambiri. Mawu oyamba ayenera kupezeka kwa aliyense, ndipo pomalizira pake chidutswacho sichingagwirizane nanu, koma anthu omwe amadziŵa bwino za gawo lanu adzatha kuzindikira.

Kodi ophunzira akukhala opusa? Global trends, internationalization.

Алексей: Mwakhala mukuwona ophunzira kwa zaka makumi angapo. Kodi ophunzira akukhala opusa kapena anzeru kuyambira zaka khumi mpaka khumi kapena chaka ndi chaka? Ku Russia, mapulofesa amadandaula nthawi zonse kuti ophunzira akudwala chaka chilichonse, ndipo sizikudziwika bwino kuti achite chiyani.

Michael: Mutha kumva zambiri zonyoza kwa ife achikulire. Mosazindikira, tili ndi chizolowezi choyembekezera kuti ophunzira atenge zaka zonse za 30 zomwe tili nazo kale. Ngati ndili ndi chidziwitso chozama kuposa momwe ndinachitira mu 1985, bwanji ophunzira alibe? Mwina chifukwa ali ndi zaka 20, mukuganiza bwanji? Ndikuganiza kuti kusintha kwakukulu m'zaka makumi angapo zapitazi kwakhala kukuchitika kwa anthu: tsopano tili ndi ophunzira ambiri ochokera kumayiko ena, kupatula aku Canada. Kale kunali anthu ambiri aku Canada chifukwa tili pafupi kwambiri ndi malire a Canada ndipo ophunzira ochokera kumeneko amatha kupita kwawo kumapeto kwa sabata. Koma tsopano pali mayunivesite ambiri abwino ku Canada, ndipo anthu aku Canada amakonda kuphunzira kuno; ochepera aiwo amabwera ku USA.

Алексей: Kodi mukuganiza kuti izi ndizochitika kwanuko kapena zapadziko lonse lapansi?

Michael: Sindikukumbukira kuti ndani kwenikweni, koma wina ananena kuti dziko ndi lafulati. Gawo lathu lakhala lapadziko lonse lapansi. Misonkhano ya ACM M'mbuyomu, adachitika ku United States kokha, kenako adaganiza zowasunga kamodzi pazaka 4 m'maiko ena, ndipo tsopano akuchitikira padziko lonse lapansi. Kusintha kumeneku kunakhudza kwambiri IEEE, monga nthawi zonse lakhala bungwe lapadziko lonse kuposa ACM. Ndipo pali mipando yamapulogalamu ochokera ku China, India, Russia, Germany ndi mayiko ena ambiri, chifukwa pali zambiri zomwe zikuchitika kulikonse tsopano.

Алексей: Koma, mwina, pali zinthu zina zoipa za internationalization wotere?

Michael: Ndinganene kuti mbali zonse zoipa sizikhudzana ndi teknoloji, koma ndale. Kalekale, vuto lalikulu linali loti US inali kuba anthu anzeru kwambiri komanso aluso kwambiri ochokera kumayiko padziko lonse lapansi. Ndipo tsopano vuto lalikulu ndi masewera a ndale pakati pa mayiko osiyanasiyana ozungulira ma visa ndi anthu othawa kwawo.

Алексей: Ndiko kuti, zotchinga ndi zinthu monga choncho. Zikumveka.

Владимир: Panokha, ndili ndi chidwi ndi njira yomwe mumatenga pophunzitsa phunziro latsopano kwa ophunzira. Pali zosankha zosiyanasiyana: mutha kuyesa choyamba kuti muwalimbikitse kuyesa china chatsopano, kapena mutha kulabadira zambiri za momwe ukadaulo wina umagwirira ntchito. Mumakonda chiyani?

Kuchita bwino ndi ophunzira

Алексей: Ndipo momwe mungapezere malire pakati pa woyamba ndi wachiwiri?

Michael: Vuto ndilakuti makalasi samayenda momwe ndingafunire. Nthawi zambiri ndimapatsa ophunzira zinthu zowerengera pasadakhale kuti azitha kuzimvetsa bwino, kuzimvetsa bwino momwe angathere, ndi kupanga mafunso okhudza mbali zomwe sakanatha kuzimvetsa. Ndiye m'kalasi mukhoza kuganizira nthawi zovuta kwambiri ndikuzifufuza pamodzi. Umu ndi momwe ndimakonda kuphunzitsa makalasi kwambiri. Koma chifukwa cha katundu amene tsopano ali pa ophunzira, sindingathe kuonetsetsa kuti akonzekereratu. Zotsatira zake, muyenera kuthera nthawi yochulukirapo pakubwerezanso zakuthupi kuposa momwe mungafune. Ngakhale zili choncho, ndimayesetsa kuti makalasi athu azilumikizana. Kupanda kutero, ndikosavuta kujambula kanema kamodzi komwe ophunzira amatha kuwonera kunyumba. Mfundo yamagulu amoyo ndikuyanjana kwa anthu. M'kalasi, ndimakonda kugwiritsa ntchito choko ndi bolodi m'malo mwa masilaidi, kupatula nthawi zina pamene chithunzi chili chovuta kuchijambula pa bolodi. Chifukwa cha izi, sindiyenera kumamatira ku dongosolo lokhazikika la maphunziro. Popeza kuti palibe dongosolo lokhwima la kupereka nkhanizo, zimenezi zimandithandiza kuti ndizigwirizana ndi omvera malinga ndi mafunso amene ndalandira. Nthawi zambiri, ndimayesetsa kupanga makalasi kukhala ogwirizana momwe ndingathere, kotero kuti zomwe ndimapereka zimadalira mafunso omwe amafunsidwa kwa ine.

Владимир: Ndizopambana. M’zondichitikira zanga, n’zovuta kuti omvera azifunsa mafunso. Ngakhale mutafunsatu kuti mufunse mafunso aliwonse, mosasamala kanthu kuti ndinu opusa bwanji kapena anzeru bwanji, amakhala chete. Kodi mumathana nazo bwanji?

Michael: Mudzaseka, koma ngati muyima mwakachetechete, posakhalitsa aliyense amasokonezeka ndipo wina adzafunsa funso. Kapena mungafunse funso losavuta laukadaulo ndi yankho la inde kapena ayi kuti muwone ngati anthu amvetsetsa zomwe zangonenedwazo. Mwachitsanzo, kodi pali mpikisano wa data pachitsanzo pamwambapa? Akuganiza choncho ndani? Ndani sakuganiza? Ndani samamvetsa kalikonse konse, chifukwa mu okwana theka la manja okha anakwera?

Vitali: Ndipo ngati simunayankhe molakwika, mumathamangitsidwa m'kalasi :)

Michael: Ngati simunayankhe kalikonse, muyenera kufunsa funso. Ndiyenera kumvetsetsa zomwe wophunzira ayenera kudziwa kuti ayankhe funso lomwe ndafunsa. Ndikufuna kuti andithandize kuwathandiza. Ndine wokonzeka kuzolowerana nawo kuti amvetsetse vutolo. Koma ngati sindikudziwa zomwe zikuchitika m'mutu mwawo, sindingathe kuchita. Ndipo ngati simupatsa ophunzira mtendere kwa nthawi yayitali yokwanira, nthawi zina pamapeto pake amafunsa mafunso oyenera, ndiko kuti, omwe amandilola kuwona zomwe zikuchitika m'mitu ya ophunzira. 

Алексей: Kodi mafunso amenewa nthawi zina amabweretsa malingaliro omwe inuyo simunawaganizirepo kale? Kodi ndi zosayembekezereka? Kodi amakulolani kuyang'ana vuto mwanjira yatsopano?

Michael: Pali mafunso amene amatsegula njira yatsopano yoperekera nkhani. Nthawi zambiri pamakhala mafunso omwe amatsogolera kumavuto osangalatsa omwe sindinakonzekere kukambirana. Ophunzira nthawi zambiri amandiuza kuti ndimakonda kuchoka pamutu izi zikachitika. Ndipo, malinga ndi iwo, nthawi zambiri iyi ndi gawo losangalatsa kwambiri la phunzirolo. Nthawi zambiri, nthawi zowerengeka chabe, ophunzira amafunsa mafunso omwe adayambitsa njira yatsopano yofufuzira ndikukula kukhala nkhani. Izi zimachitika nthawi zambiri pokambirana ndi ophunzira osati m'kalasi, koma nthawi zina zimachitika m'makalasi. 

Алексей: Ndiye ophunzirawo adakufunsani mafunso potengera zomwe zinali zotheka kufalitsa nkhani?

Michael: Inde. 

Vitali: Kodi mumacheza kangati ndi ophunzira? Kodi ndi liti pamene akufuna kuphunzira zambiri kuposa zimene zinakambidwa m’phunzirolo?

Michael: Ndi ophunzira anga omaliza maphunziro - nthawi zonse. Ndili ndi pafupifupi 5 kapena 6 a iwo, ndipo timakambirana nawo zinazake nthawi zonse. Ndipo zokambilana zamtunduwu ndi ana asukulu amene amangopezeka m’makalasi anga sizofala. Ngakhale ndikulakalaka kuti izi zichitike pafupipafupi. Ndikukayikira kuti akungoopa kubwera ku faculty nthawi yantchito. Semesita iliyonse, ophunzira ena amatha kuthana ndi vuto lamalingaliro ili, ndipo nthawi zonse zimakhala zosangalatsa kukambirana nawo mukamaliza kalasi. N’zoona kuti ophunzira onse akanakhala olimba mtima chonchi, sindikanakhala ndi nthawi yokwanira. Ndiye mwina zonse zikuyenda momwe ziyenera kukhalira. 

Vitali: Kodi mumatha bwanji kupeza nthawi yolankhulana ndi ophunzira? Monga ndikudziwira, ku USA aphunzitsi ali ndi ntchito zambiri - kupempha thandizo ndi zina zotero. 

Michael: Moona mtima, kugwira ntchito ndi ophunzira ndi gawo la ntchito yanga yomwe ndimakonda kwambiri. Kotero ndili ndi chilimbikitso chokwanira pa izi. Nthawi zambiri ndimakhala muofesi yanga ndimakhala pamisonkhano yamitundumitundu. Ndi chilimwe tsopano, kotero kuti ndondomeko yanga sikhala yotanganidwa, koma m'chaka cha sukulu, tsiku lililonse kuyambira 9 mpaka 17 ndimakhala ndi zonse. Ntchito yofufuza, ndemanga, zopereka - pa zonsezi pali madzulo ndi kumapeto kwa sabata. 

Momwe mungapitirizire kukonzekera maphunziro atsopano ndi mabuku.

Алексей: Kodi panopa mukupitiriza kuphunzitsa maphunziro aliwonse omwe mwakhala mukuphunzitsa kwa nthawi yaitali? Chinachake ngati chiyambi cha Computer Science.

Michael: Chinthu choyamba chimene chimabwera m'maganizo apa ndi maphunziro a zilankhulo zamapulogalamu. 

Алексей: Kodi maphunzirowa akusiyana bwanji ndi momwe analili zaka 10, 20, 30 zapitazo? Mwina chomwe chili chosangalatsa kwambiri pano si tsatanetsatane wa maphunziro enaake, koma momwe zimakhalira.

Michael: Maphunziro anga pa zilankhulo zamapulogalamu anali achilendo panthawi yomwe ndidapanga. Ndinayamba kuliwerenga chakumapeto kwa zaka za m’ma 1980, m’malo mwa mnzanga, Doug Baldwin (Doug Baldwin). Mutu wa maphunzirowo unali wogwirizana kwambiri ndi luso langa, koma pamene anachoka, ndinali woyenerera kwambiri kuphunzitsa maphunzirowo. Sindinakonde mabuku aliwonse omwe analipo panthawiyo, motero ndinamaliza kulemba ndekha buku la maphunzirowa. (Zolemba mkonzi: tikukamba za bukuli "Programming Language Pragmatics") Panopa imagwiritsidwa ntchito m'mayunivesite oposa 200 padziko lonse lapansi. Njira yanga ndi yachilendo chifukwa imasakaniza mwadala mavuto a kamangidwe ka chinenero ndi kukhazikitsa, ndipo imamvetsera kwambiri kugwirizana pakati pa mbali zonse zomwe zingatheke. Njira yoyambira sinasinthidwe, monganso ndi malingaliro ambiri oyambira: zotsatiridwa, malo amazina, modularity, mitundu. Koma zilankhulo zomwe mfundozi zimasonyezedwa zasintha kwambiri. Pamene maphunzirowa adalengedwa koyamba, panali zitsanzo zambiri ku Pascal, koma lero ophunzira anga ambiri sanamvepo za chinenerochi. Koma amadziwa Swift, Go, Rust, kotero ndiyenera kulankhula za zilankhulo zomwe zikugwiritsidwa ntchito masiku ano. Komanso, ophunzira tsopano amadziwa bwino zilankhulo zolembera, koma nditayamba kuphunzitsa maphunzirowa, zonse zinali zokhudzana ndi zilankhulo zophatikizidwa. Tsopano tikufunikira zinthu zambiri za Python, Ruby komanso Perl, chifukwa izi ndizomwe zalembedwa masiku ano, ndipo pali zinthu zambiri zosangalatsa zomwe zikuchitika m'zinenero izi, kuphatikizapo m'munda wa mapangidwe a chinenero. 

Vitali: Ndiye funso langa lotsatira lidzakhala logwirizana ndi lapitalo. Kodi kukhalabe m'dera lino? Ndikukayikira kuti kukonzanso maphunziro ngati awa kumafuna ntchito yambiri - muyenera kumvetsetsa zinenero zatsopano, kumvetsetsa mfundo zazikulu. Kodi mumachita bwanji izi?

Michael: Sindingadzitamande kuti nthawi zonse ndimapambana 100%. Koma nthawi zambiri ndimangochita zomwe wina aliyense amachita - kuwerenga pa intaneti. Ngati ndikufuna kumvetsetsa Rust, I Google, pitani patsamba la Mozilla ndikuwerenga buku lomwe laikidwa pamenepo. Izi ndi zina mwazinthu zomwe zimachitika pakukula kwamalonda. Ngati tilankhula za sayansi, ndiye kuti muyenera kutsatira malipoti pamisonkhano yayikulu. 

Mgwirizano pakati pa bizinesi ndi maphunziro

Vitali: Tiyeni tikambirane za kugwirizana pakati pa bizinesi ndi kafukufuku wa sayansi. Pamndandanda wanu wantchito, ndapeza zolemba zingapo zokhudzana ndi cache. Ndikumvetsa kuti ma cache consistency algorithms anali osakhazikika panthawi yomwe amasindikizidwa? Kapena osafalikira mokwanira. Kodi malingaliro anu anali ochuluka bwanji pochita?

Michael: Sindikutsimikiza kwenikweni kuti ndi zofalitsa ziti zomwe mukunena. Ndagwira ntchito pang'ono ndi ophunzira anga Bill Bolosky (William Bolosky) ndi Leonidas Kontotanassis (Leonidas Kontothanassis) koyambirira kwa 1990s pakuwongolera kukumbukira makina a Neumann. Panthawiyo, bizinesi inali isanamvetsetse momwe mungapangire makina opangira ma multiprocessor: kodi ndi koyenera kupanga chithandizo chofikira kukumbukira kwakutali pamlingo wa hardware, kodi ndi koyenera kuti kukumbukira kugawidwe, kodi n'zotheka kutsegula cache kuchokera? kukumbukira kwakutali, kapena ndikofunikira kusuntha masamba muchipinda chogwiritsira ntchito? Bill ndi Leonidas onse adagwira ntchito m'derali ndikufufuza njira popanda kutsitsa kache yakutali. Izi sizinali zogwirizana mwachindunji ndi kugwirizana kwa cache, koma zinali ntchito pa kasamalidwe ka kukumbukira kwa NUMA, ndipo pambuyo pake njira zamakono zoyika masamba m'machitidwe amakono zidakula kuchokera pa izi. Ponseponse, Bill ndi Leonidas adagwira ntchito yofunika kwambiri, ngakhale kuti sanali otchuka kwambiri m'derali - panali anthu ena ambiri omwe amagwira ntchito yofanana panthawiyo. Pambuyo pake, ndinagwira ntchito pamutu wokhudzana ndi mgwirizano wa cache muzochitika za hardware transaction memory. Gulu lomwe ndidagwirapo nawo pavutoli lidamaliza kulandira ma patent angapo. Pali malingaliro osangalatsa kumbuyo kwawo, koma sindikuganiza kuti atha kugwiritsidwa ntchito. Mwanjira ina, ndizovuta kwa ine kuweruza phindu lawo. 

Алексей: Pachifukwa ichi, funso laumwini: Kodi ndi kofunika bwanji kwa inu kuti malingaliro anu agwiritsidwe ntchito? Kapena simukuziganizira?

Michael: Ndimakonda kufunsa funsoli poyankhulana ndi anthu ena, olembetsa kapena ofuna kulowa nawo gawoli. Sindikuganiza kuti pali yankho lolondola ku funsoli. Anthu omwe amachita zinthu zabwino amatha kukhala ndi zolinga zosiyana kwambiri. Ndimakopeka ndi mavuto chifukwa ndimawapeza osangalatsa, osati chifukwa cha mapindu ake. Koma kumbali ina, chinthu china chosangalatsa chikapezabe ntchito, ndimakonda kwambiri. Choncho sikophweka pano. Koma kumayambiriro kwa ntchito yanga, sindimayendetsedwabe ndi lingaliro la kutha kwa dziko lapansi, koma ndi mgwirizano wa lingaliro ndi chikhumbo chofufuza ndikuwona zomwe zimachokera. Ngati pamapeto pake zimapereka zotsatira zothandiza, zabwino. 

Алексей: Chifukwa cha maphunziro anu ndi luso lanu, ndinu okhoza bwino kuposa ambiri kuweruza phindu la malingaliro a anthu ena. Mutha kuwafananiza ndikuzindikira zomwe zimagwira ntchito bwino ndi zomwe. Ndikukhulupirira kuti muli ndi malingaliro pazinthu zomwe zikugwiritsidwa ntchito pano ndi opanga akuluakulu monga Intel. Mukuona kwanu, kodi njira zomwe makampaniwa akuchitira ndi zolondola bwanji?

Michael: Kuchita masewera olimbitsa thupi nthawi zonse kumakhudza zomwe zingakhale bwino pamalonda, ndiko kuti, kupanga phindu, ndipo muyenera kufunsa wina za izo. Ntchito yanga makamaka imabweretsa zofalitsa, ndipo m'munda wa machitidwe ogwiritsira ntchito amawunikidwa malinga ndi zizindikiro za ntchito: liwiro, kugwiritsa ntchito mphamvu, kukula kwa code. Koma nthawi zonse zinkawoneka kwa ine kuti zotulukapo zowoneka bwinozi zimangowonjezeredwa m'nkhani kuti zisindikizidwe, ndipo zolinga zenizeni za anthu pantchito ndi zokongola. Ochita kafukufuku amayesa mayankho kuchokera ku luso lazojambula, amasamala za momwe malingaliro aliri okongola, ndipo amayesa kupanga chinthu chabwino kuposa njira zomwe zilipo kale. Ochita kafukufuku amayendetsedwa ndi zolinga zaumwini, zaumwini, zokongoletsa. Koma simungalembe za izi m'nkhaniyi; zinthu izi sizotsutsana ndi komiti ya pulogalamuyo. Mwamwayi, njira zokongola nthawi zambiri zimakhalanso zachangu komanso zotsika mtengo. Anzanga khumi ndi awiri tinakambirana nkhaniyi zaka 15 zapitazo ndipo tinamaliza kulemba nkhani za izo. Ndikuganiza kuti mutha kuzipeza pano, zimatchedwa "Momwe mungawunikire kafukufuku wamakina" kapena chinachake chonga icho, chiri ndi olemba oposa khumi ndi awiri. Iyi ndi nkhani yokhayo yomwe ine ndine wolemba pamodzi Sasha Fedorova, kotero ngati mutafufuza dzina lake pamndandanda wanga wa zofalitsa, mudzapeza zomwe mukufuna. Imakamba za kuwunika kafukufuku wamachitidwe ndi momwe kukongola kulili kofunikira. 

Алексей: Choncho pali kusiyana pakati pa muyezo wa zomwe zimaonedwa kuti ndi zabwino mu sayansi ndi bizinesi. Sayansi imayesa magwiridwe antchito, kugwiritsa ntchito mphamvu, TDP, kusavuta kukhazikitsa, ndi zina zambiri. Kodi muli ndi mwayi wochita kafukufuku wamtunduwu ku yunivesite? Kodi muli ndi labotale yokhala ndi makina osiyanasiyana ndi zomanga zosiyanasiyana momwe mungayesere?

Michael: Inde, dipatimenti yathu ili ndi makina osiyanasiyana osangalatsa. Nthawi zambiri amakhala ang'onoang'ono, timakhala ndi gulu laling'ono komanso makina ambiri opangira ma multiprocessor okhala ndi ma accelerator osiyanasiyana. Kuphatikiza apo, sukuluyi ili ndi malo akulu apakompyuta omwe amatumikira asayansi ochokera m'magawo angapo osiyanasiyana. Ili ndi ma node pafupifupi chikwi ndi ma cores zikwi makumi awiri, onse pa Linux. Ngati pakufunika, mutha kugula AWS nthawi zonse. Chifukwa chake tilibe zoletsa zazikulu ndi hardware. 

Алексей: Zinali bwanji zaka makumi atatu zapitazo? Kodi panali mavuto pamenepo?

Michael: Zinali zosiyana pang'ono pamenepo. Chakumapeto kwa zaka za m'ma 1980, sayansi inkaonedwa kuti ndi yochepa kwambiri pakugwiritsa ntchito makompyuta. Pofuna kuthetsa vutoli, National Science Foundation (National Science Foundation) adapanga pulogalamu yoyeserera yoyeserera (Coordinated Experimental Research, CER). Cholinga cha pulogalamuyi chinali kupereka zida zamakompyuta zamadipatimenti a Computer Science, ndipo zasintha kwambiri. Ndi ndalama zomwe anapereka, ife ku yunivesite ya Rochester tinagula BBN Butterfly ya 1984-knot mu 128, ichi chinali chaka chimodzi ndisanafike kumeneko. Pa nthawiyo inali njira yayikulu kwambiri padziko lonse lapansi yopangira ma multiprocessor okhala ndi kukumbukira kogawana. Inali ndi mapurosesa 128, iliyonse pa bolodi la amayi osiyana, ndipo inali ndi ma rack anayi. Purosesa iliyonse inali ndi megabyte ya kukumbukira, 128 megabytes ya RAM inali kuchuluka kosayerekezeka panthawiyo. Pa makinawa tinagwiritsa ntchito kutseka kwa MCS kwa nthawi yoyamba. 

Алексей: Kotero, ngati ndikumvetsani bwino, ndiye pakali pano vuto la hardware lathetsedwa? 

Michael: Kawirikawiri, inde. Pali chenjezo zingapo: choyamba, ngati mukupanga makompyuta pamlingo wa chip, ndizovuta kuchita m'malo ophunzirira chifukwa pali zida zabwinoko zochitira bizinesi. Ngati mukufuna chilichonse chocheperako ma nanometer 10, muyenera kuyitanitsa kwa wina. M'derali ndizosavuta kukhala wofufuza ku Intel. Ngati mukugwira ntchito yolumikizirana ndi tchipisi kapena kukumbukira-boma, mupeza matekinoloje mubizinesi omwe sanakhalepo mu sayansi, ndiye kuti muyenera kupanga mgwirizano. Mwachitsanzo, Stephen Swanson (Steven Swanson) adapangidwa mgwirizano wotere kwa matekinoloje atsopano a kukumbukira. Fomu iyi simagwira ntchito nthawi zonse, koma nthawi zina imatha kukhala yopambana. Kuphatikiza apo, mu sayansi kupanga makina amphamvu kwambiri apakompyuta ndizovuta kwambiri. Ntchito zazikulu kwambiri zamakompyuta zomwe zili ku US, Japan ndi China zonse zimangoyang'ana bizinesi. 

Kuchita bwino kwa malingaliro. MCS, MS, CLH, JSR 166, kugwira ntchito ndi Doug Lee ndi zina.

Vitali: Mwalankhula kale za momwe munayambira kugwira ntchito pa ma aligorivimu olumikizana. Muli ndi nkhani ziwiri zodziwika bwino za Kutsekeka kwa MCS и Michael-Scott queue (MS), zomwe mwanjira ina zidakhazikitsidwa mu Java. (Chidziwitso cha mkonzi: zofalitsa zonse zitha kuwonedwa kugwirizana). Kumeneko kutsekereza uku kudakhazikitsidwa ndi zosintha zina ndipo zidachitika CHL loko, ndipo mzerewo unakhazikitsidwa monga momwe unafunira. Koma zaka zambiri zinadutsa pakati pa kufalitsidwa kwa nkhani zanu ndi ntchito zake zothandiza. 

Алексей: Zikuoneka ngati zaka 10 pa nkhani ya pamzere.

Michael: Kodi izi zisanachitike mu Java standard library?

Vitali: Inde. Munachita chiyani kuti izi zitheke? Kapena sanachite chilichonse?

Michael: Ndikhoza kukuuzani momwe MS Queue inalowera mu Java 5. Zaka zingapo zisanatuluke, ndinagwira ntchito ndi gulu la Mark Moyers ku Sun Microsystems mu labu yawo pafupi ndi Boston. Anakonza msonkhano wa anthu omwe amawadziwa omwe akugwira ntchito pazovuta zosangalatsa mu multithreading chifukwa ankafuna kupeza mitu yomwe angagulitse ku kampani yawo. Kumeneko ndi kumene ndinakumana koyamba ndi Doug Lea. Ine ndi Doug ndi anthu ena pafupifupi 25 ochokera ku Sun tinali pamodzi kukambirana nkhani ya Doug Mtengo wa JSR166, yomwe pambuyo pake idakhala java.util.concurrent. Ali m'njira, Doug adanena kuti akufuna kugwiritsa ntchito mzere wa MS, koma chifukwa cha izi amafunikira chowerengera cha kuchuluka kwa zinthu zomwe zili pamzere wa mawonekedwe. Ndiko kuti, izi zikanayenera kuchitidwa ndi njira ina, atomiki, yolondola komanso yachangu. Ndidapereka lingaliro longowonjezera manambala amtundu ku ma node, kutenga nambala ya nodi yoyamba ndi yomaliza ndikuchotsa imodzi pa imzake. Doug anakanda mutu wake, nati “bwanji,” ndipo pamapeto pake anachitadi zimenezo. Tinakambirana za kugwiritsa ntchito njirayi mulaibulale, koma Doug adagwira ntchito yambiri yekha. Zotsatira zake, adakwanitsa kukhazikitsa chithandizo chabwino kwambiri cha multithreading ku Java. 

Алексей: Ndiye, ngati ndimvetsetsa bwino, njira ya .size() imayenera kukhala gawo la mizere yokhazikika, ndipo imayenera kukhala ndi zovuta za algorithmic za O(1)?

Michael: Inde, ndipo kuwonjezera pa izi, counter counter ikufunika.

Алексей: Chifukwa ngati mutcha njira ya .size () ku Java, zotsatira zake zikuyembekezeka kupezeka nthawi yomweyo osati kutengera kukula kwenikweni kwa zosonkhanitsira. Ndikuwona, zikomo.

Michael: Zaka zingapo pambuyo pake ndinali ndikugwira ntchito pazambiri zama data ndi wophunzira wanga Bill Scherer - kwenikweni, izi ndi zomwe ndikhala ndikukambirana. lipoti pa Hydra. Doug anabwera kwa ife natiuza kuti akhoza kuzigwiritsa ntchito mu Java Executor Framework. Pamodzi ndi Bill, adakhazikitsa njira ziwiri, zomwe zimatchedwa mizere yachilungamo komanso yopanda chilungamo. Ndinawalangiza pa ntchitoyi, ngakhale kuti sindinatenge nawo mbali polemba code yeniyeni. Chotsatira chake, liwiro la executors lawonjezeka kwambiri. 

Владимир: Kodi mwakumana ndi kukhazikitsidwa kolakwika kwa ma aligorivimu anu kapena zopempha kuti muwonjezere zatsopano? Nthawi zambiri, machitidwe ayenera kugwirizana ndi chiphunzitso, koma nthawi zambiri amasiyana. Tiyerekeze kuti mwalemba algorithm, ndipo pamapepala imagwira ntchito, koma anthu omwe akugwira nawo ntchitoyo anayamba kukufunsani zina zambiri kapena mtundu wina wa kusintha kwa ndondomekoyi. Kodi inu munayamba mwakumanapo ndi mikhalidwe yoteroyo?

Michael: Chitsanzo chokhacho chomwe wina adabwera kwa ine ndikufunsa "momwe angagwiritsire ntchito" ndi funso la Doug, lomwe ndinanena kale. Koma pakhala pali zochitika zingapo pamene zosintha zosangalatsa zapangidwa kuti zigwirizane ndi zosowa zenizeni. Mwachitsanzo, gulu la K42 ku IBM linasintha loko ya MCS ndikuipanga kukhala yokhazikika kotero kuti panalibe chifukwa chodutsira mzere wa pamzere kupita ndi mtsogolo kuti mupeze ndi kumasula machitidwe. Chifukwa cha mawonekedwe okhazikika awa, lingaliro lomwe linali lokongola m'lingaliro linayamba kugwira ntchito. Ndizodabwitsa kuti sanasindikizepo nkhani yokhudza izi, ndipo ngakhale adalandira chilolezo, pambuyo pake adachisiya. Lingalirolo linali lodabwitsa, ndipo ndimayesetsa kukambirana nalo ngati kuli kotheka. 

Pakhala pali zochitika zina pomwe anthu asintha ma algorithms omwe ndasindikiza. Mwachitsanzo, mzere wa MS uli ndi njira yokhazikitsira magawo awiri, zomwe zikutanthauza kuti panali ma CAS awiri panjira yovuta ya mzerewo. Pamagalimoto akale, CAS inali yokwera mtengo kwambiri. Intel ndi opanga ena awakonza bwino posachedwa, koma nthawi ina awa anali malangizo ozungulira 30, kotero kukhala ndi opitilira m'modzi panjira yovuta sikunali koyenera. Zotsatira zake, mzere wosiyana unapangidwa womwe unali wofanana ndi mzere wa MS, koma womwe unali ndi ntchito imodzi yokha ya atomiki panjira yovuta. Izi zidatheka chifukwa chakuti nthawi ina ntchitoyo imatha kutenga nthawi ya O(n), osati O(1). Sizinali zotheka, koma zotheka. Izi zidachitika chifukwa chakuti nthawi zina ma aligorivimu amadutsa pamzere kuyambira pachiyambi mpaka pomwe pano pamzerewu. Mwambiri, algorithm idakhala yopambana kwambiri. Monga ndikudziwira, sikugwiritsidwa ntchito kwambiri, mwina chifukwa chakuti ma atomiki amafunikira zinthu zochepa kwambiri kuposa kale. Koma lingalirolo linali lalikulu. Ndimakondanso ntchito ya Dave Dice wochokera ku Oracle. Chilichonse chimene amachita ndi chothandiza ndipo amagwiritsa ntchito chitsulo mochenjera kwambiri. Iye anali ndi dzanja mu zambiri za NUMA-aware synchronization algorithms ndi multi-threaded data structures. 

Владимир: Mukalemba ma aligorivimu kapena kuphunzitsa ophunzira, zotsatira za ntchito yanu siziwoneka nthawi yomweyo. Anthu ammudzi amafunikira nthawi kuti adziwe bwino, tinene, nkhani yatsopano. Algorithm yatsopano siyipeza ntchito nthawi yomweyo. 

Michael: Sizikudziwika nthawi yomweyo ngati nkhaniyo idzakhala yofunika kapena ayi. Ndikuganiza kuti zingakhale zosangalatsa kuchita kafukufuku wa mapepala omwe apambana mphoto pamisonkhano. Ndiko kuti, yang’anani nkhani zimene anthu a m’makomiti a pulogalamu pa nthawi ina ankaziona ngati zabwino kwambiri. Muyenera kuyesa kuwerengera kuchuluka kwa maulalo ndi momwe bizinesi ikukhudzira momwe zolembazi zidakhalira zaka 10, 20, 25. Ndikukayika kuti pangakhale mgwirizano wamphamvu pakati pa ziwirizi. Sizingakhale ziro, koma mwina zikhala zofooka kwambiri kuposa momwe timafunira. Malingaliro ambiri amakhalabe osadziwika kwa nthawi yayitali asanafalikire. Mwachitsanzo, tiyeni tione transaction memory. Zaka zoposa 10 zidadutsa kuchokera pomwe nkhani yoyambirira idasindikizidwa mpaka pomwe anthu adayamba kupanga makina nayo. Ndipo pamaso pa maonekedwe a kukumbukira ichi mu malonda malonda - ndi onse 20. Kwa nthawi yaitali kwambiri palibe amene analabadira nkhani, ndiyeno chiwerengero cha maulalo izo chinawonjezeka kwambiri. Zingakhale zovuta kulosera izi pasadakhale. Komano, nthawi zina malingaliro amapeza kukhazikitsidwa nthawi yomweyo. Zaka zingapo zapitazo, ndidalemba pepala ndi a Joe Izraelevitz ku DISC yomwe idapereka tanthauzo latsopano la kutsimikizika kwazinthu zolimbikira zomwe zingagwiritsidwe ntchito kompyuta itawonongeka. Nkhaniyi ndinaikonda kuyambira pachiyambi, koma idadziwika kwambiri kuposa momwe ndimayembekezera. Linagwiritsidwa ntchito ndi magulu angapo osiyanasiyana ndipo potsirizira pake linakhala tanthawuzo lokhazikika la zomangamanga zolimbikira. Zomwe, ndithudi, ndi zabwino.

Владимир: Kodi pali njira zilizonse zomwe mumagwiritsa ntchito poyesa? Kodi mumayesanso kuyesa zolemba zanu ndi ophunzira anu? Ponena za ngati munthu amene mwamuphunzitsayo akupita njira yoyenera.

Michael: Mofanana ndi wina aliyense, ndimamvetsera kwambiri zimene ndikuchita panopa. Apanso, monga wina aliyense, nthawi zina ndimayang'ana Google Scholar kuti ndiwone ngati mapepala anga am'mbuyomu akutchulidwa, koma ndichochidwi. Nthawi zambiri ndimakhudzidwa kwambiri ndi zomwe ophunzira anga akuchita tsopano. Zikafika pakuwunika ntchito zomwe zikuchitika pano, mbali yake ndi zokongoletsa, zomwe zili zokongola ndi zomwe sizili. Ndipo pamlingo watsiku ndi tsiku, mafunso otseguka amakhala ndi gawo lalikulu. Mwachitsanzo, wophunzira amabwera kwa ine ndi graph ya zotsatira zina, ndipo tikuyesera kumvetsetsa komwe khalidwe lachilendo la graph linachokera. Mucikozyanyo, mumulimo wesu tulakonzya kubikkila maano kuzintu nzyotutakonzyi kuzimvwisya. 

Transaction memory

Vitali: Mwina tingalankhule pang'ono za kukumbukira transaction?

Michael: Ndikuganiza kuti ndibwino kunena pang'ono chifukwa ndimayesetsa kwambiri. Uwu ndi mutu womwe ndili nawo zofalitsa zambiri kuposa wina uliwonse. Koma nthawi yomweyo, modabwitsa, nthawi zonse ndimakhala wokayika kwambiri za kukumbukira kwa transaction. M'malingaliro anga, nkhani ya Herlihy ndi Moss (M. Herlihy, J. E. B. Moss) linasindikizidwa nthaŵi yake isanakwane. Kumayambiriro kwa zaka za m'ma 1990, adanena kuti kukumbukira zochitika kungathandize olemba mapulogalamu aluso kugwira ntchito pazinthu zamitundu yambiri, kotero kuti izi zitha kugwiritsidwa ntchito ngati malaibulale ndi olemba mapulogalamu wamba. Ndiko kuti, zingakhale zothandiza kwa Doug Lee kuchita JSR 166 yake. Koma kukumbukira kusinthika sikunapangidwe kuti pulogalamu yamitundu yambiri ikhale yosavuta. Koma izi ndi momwe zinayambira kumayambiriro kwa zaka za m'ma 2000, pamene zinafala kwambiri. Zinalengezedwa ngati njira yothetsera vuto la mapulogalamu ofanana. Njira imeneyi nthawi zonse yakhala ikuwoneka yopanda chiyembekezo kwa ine. Memory transaction imangopangitsa kuti zikhale zosavuta kulemba ma data ofanana. Izi, zikuwoneka kwa ine, ndi zomwe adakwanitsa. 

Za vuto lolemba ma code amitundu yambiri

Алексей: Zosangalatsa kwambiri. Zikuwoneka kuti pali chotchinga china pakati pa opanga mapulogalamu okhazikika ndi omwe amatha kulemba nambala yamitundu yambiri. Chaka chatha, ndinalankhula kangapo ndi anthu omwe anali kugwiritsa ntchito ndondomeko ya algorithmic. Mwachitsanzo, ndi Martin Thomson, komanso opanga mapulogalamu omwe amagwira ntchito pama library okhala ndi ulusi wambiri. (Zolemba mkonzi: Martin Thompson ndi wopanga mapulogalamu otchuka kwambiri, adalemba Zosokoneza и Aeron. Ndipo iyenso watero lipotilo pamsonkhano wathu wa Joker 2015, kujambula kanema kupezeka pa YouTube. Iye ali yemweyo anatsegula msonkhano uno kujambula mawu ofunika ziliponso). Chovuta chachikulu, akuti, ndikupanga ma aligorivimu mwachangu komanso osavuta kugwiritsa ntchito. Ndiko kuti, akuyesera kuthana ndi chotchingachi ndikukopa anthu ambiri momwe angathere kuderali. Mukuganiza bwanji za izo?

Michael: Ili ndilo vuto lalikulu la multithreading: momwe mungakwaniritsire ntchito zapamwamba popanda kuwonjezera zovuta za dongosolo. 

Алексей: Chifukwa akamayesetsa kupewa zovuta, algorithm imakhala yocheperako konsekonse.

Michael: Chinsinsi apa ndizomwe zidapangidwa bwino. Zikuwoneka kwa ine kuti ichi ndiye chinthu chachikulu pamakompyuta ngati gawo. Butler Lampson amakonda kugwiritsa ntchito mawuwa, ndipo amatitcha "amalonda a zinthu zongoyerekeza." Ukadaulo wosavuta kulibe lero. Mapurosesa omwe timagwiritsa ntchito ali ndi ma transistors 10 biliyoni - kuphweka sikuli kofunikira. Panthawi imodzimodziyo, ISA ndi yophweka kwambiri kuposa purosesa, popeza tinagwira ntchito kwa nthawi yaitali kuti tipereke ntchito yapamwamba komanso mawonekedwe osavuta. Koma sikuti zonse zili bwino ndi iye. Vuto lomwelo lili ndi ma accelerator omwe akuwonekera pamsika. Mafunso amawuka - momwe mungapangire mawonekedwe oyenera a GPU, makina obisala, kuponderezana, kachipangizo ka transcoding, makina a algebra, kapena FPGA yosinthika kwambiri. Momwe mungapangire mawonekedwe omwe amapangitsa chida kukhala chosavuta kugwiritsa ntchito ndikubisa zovuta? Sichidzachichotsa, koma m'malo mwake chibiseni kwa pulogalamu yosavuta. 

Алексей: Monga ndikumvetsetsa, tidakali ndi chotchinga pakumvetsetsa zotsatiridwa. Tiyeni titenge chitsanzo cha kukumbukira; pa gawo lathu la chitukuko cha sayansi ndi teknoloji, ichi ndi chimodzi mwazinthu zazikulu. Chifukwa chake, opanga mapulogalamu onse amagawidwa m'magulu awiri: gawo lalikulu ndi la omwe sakumvetsetsa, ndipo gawo laling'ono ndi omwe amamvetsetsa, kapena kuganiza kuti amvetsetsa. 

Michael: Limenelo ndi funso labwino - kodi aliyense wa ife amamvetsadi chitsanzo cha kukumbukira?

Vitali: Makamaka mu C++.

Michael: Lankhulani ndi Hans Boehm nthawi ina. Iye ndi m'modzi mwa anthu anzeru kwambiri omwe ndimawadziwa, katswiri wotsogola wa zitsanzo zamakumbukiro. Adzakuuzani nthawi yomweyo kuti pali zambiri zomwe sakuzimvetsa. Koma ngati tibwerera ku nkhani ya abstractions, ndiye, mwa lingaliro langa, lingaliro lofunika kwambiri pazambiri zamakumbukiro pazaka 30 zapitazi lidawonetsedwa. m'mawu a Sarita Adve. (Chidziwitso cha mkonzi: mndandanda wathunthu wazofalitsa ulipo kugwirizana).

Алексей: Funso langa ndilakuti: kodi chotchinga ichi chimachokera ku chikhalidwe chenicheni cha lingaliro? 

Michael: Ayi. Sarita adatsimikiza kuti ndi njira yoyenera, mutha kubisala zovuta zonse, kupeza magwiridwe antchito apamwamba ndikupatsa wopanga pulogalamu API yosavuta. Ndipo ngati mutsatira API iyi, mutha kukwaniritsa kusasinthasintha. Ndikuganiza kuti ichi ndi chitsanzo choyenera. Lembani ma code popanda mipikisano ya data ndikupeza kusasinthika kotsatizana. Inde, pofuna kuchepetsa mwayi wothamanga, pamafunika zida zapadera, koma imeneyo ndi nkhani ina. 

Владимир: Kodi pakhala nthawi zina pantchito yanu pomwe vuto lomwe limawoneka kuti latha mwadzidzidzi linasanduka tsoka, kapena zidapezeka kuti vutoli silingatheke? Mwachitsanzo, m'lingaliro mukhoza kuwerengera nambala iliyonse kapena kudziwa ngati nambala iliyonse ndi yopambana. Koma pochita izi zitha kukhala zovuta kuchita; ndi zida zamakono zimakhala zovuta kuwerengera manambala. Kodi zimenezi zachitikanso kwa inu?

Michael: Sindikukumbukira nthawi yomweyo chilichonse chonga chimenecho. Pakhala pali nthaŵi zina zimene zinkawoneka kwa ine kuti kunalibe chochita m’dera linalake, koma kenaka chinachake chatsopano ndi chosangalatsa chinachitika kumeneko. Mwachitsanzo, ndimaganiza kuti malo okhala pamzere wopanda malire anali atakula kale. Pambuyo pakusintha kangapo pamzere wa MNS, palibe chomwe chinachitikanso. Kenako Morrison (Adam Morrison) ndi Afek (Yehuda Afek) anapanga Mtengo wa LCRQ. Zinawonekeratu kuti mzere wopanda malire wa mizere yambiri unali zotheka, kumene nthawi zambiri kunali kokha malangizo otengera ndi owonjezera pa njira yovuta. Ndipo izi zidapangitsa kuti zitheke kukwaniritsa dongosolo lakuchita bwino kwambiri. Sikuti sitikudziwa kuti kukweza ndi kuonjezera ndi chinthu chothandiza kwambiri. Eric Freudenthal analemba za izi mu ntchito yake pa Ultracomputer ndi Allan Gottlieb kumapeto kwa zaka za m'ma 1980, koma zinali za mizere yochepa. Morrison ndi Afek adatha kugwiritsa ntchito kutengera-ndi-increment pamzere wopanda malire.

Zomangamanga zatsopano. Kodi chigonjetso cha kukumbukira kwamalonda chayandikira?

Владимир: Kodi mukuyang'ana njira zatsopano zomangira zomwe zingakhale zothandiza pama algorithms? 

Michael: Inde, pali zinthu zambiri zomwe ndikufuna kuti zichitike. 

Владимир: Mwachitsanzo, mtundu wanji?

Michael: Choyambirira, zowonjezera zochepa zokumbukira zamtundu wa hardware mu ma processor a Intel ndi IBM. Makamaka, ndikufuna kuti katundu wosagulitsa ndi sitolo zomwe zangopezeka kuti zizipezeka nthawi yomweyo pakachitika. Nthawi yomweyo amatsogolera ku malupu muzochitika-zisanachitike motsatizana, kuti zikhale zovuta. Koma ngati musunga magawo ang'onoang'ono, pali zinthu zambiri zosangalatsa zomwe mungachite kunja kwa malonda pamene zikuchitika. Sindikudziwa kuti izi zingakhale zovuta bwanji kuti ndikwaniritse, koma zingakhale zothandiza kwambiri. 

Chinthu chinanso chothandiza ndikutsegula cache kuchokera pamtima wakutali. Ndikuganiza kuti posachedwa izi zichitika. Tekinoloje iyi idzalola kupanga machitidwe okhala ndi kukumbukira kosiyana. Zingakhale zotheka kusunga, kunena, ma terabytes 100 a kukumbukira kosasunthika mu rack, ndipo makina ogwiritsira ntchito pawokha amatha kusankha kuti ndi zigawo ziti za kukumbukirako zomwe ziyenera kugwirizana ndi malo a adiresi a mapurosesa. Izi zitha kukhala zothandiza kwambiri pamakompyuta apamtambo, chifukwa zitha kulola kukumbukira kwakukulu kuperekedwa ku ntchito zomwe zikufunika. Ndikuganiza kuti wina adzachita.

Vitali: Kuti nditsirize kuyankhula za kukumbukira kwamalonda, ndili ndi funso linanso pamutuwu. Kodi makumbukidwe osinthika pamapeto pake adzalowa m'malo mwa ma data okhala ndi ulusi wambiri?

Michael: Ayi. Zochita ndi njira yongopeka. Pa mlingo wa mapulogalamu awa ndi maloko a atomiki, koma mkati mwake ndi zongopeka. Kuneneratu kotereku kumagwira ntchito ngati zolingalira zambiri zili zolondola. Chifukwa chake, kukumbukira kumagwira ntchito bwino ngati ulusi sunagwirizane, ndipo muyenera kuwonetsetsa kuti palibe zolumikizana. Koma ngati uthenga wayamba pakati pa ulusi, kugulitsa sikuthandiza kwenikweni. Ndiloleni ndifotokoze, tikukamba za mlanduwu pamene zochitika zimakutidwa ndi ntchito yonse ya atomiki. Zitha kugwiritsidwabe ntchito bwino ngati zigawo zama data amitundu yambiri. Mwachitsanzo, ngati mukufuna mawu atatu CAS, ndipo muyenera multithread atatu ang'onoang'ono aligorivimu moona multithreaded aligorivimu amene amagwira ntchito ndi ulusi makumi awiri nthawi imodzi. Nthawi zambiri, kuchitapo kanthu kungakhale kothandiza, koma sikungathetse kufunikira kokonzekera bwino ma data amitundu yambiri. 

Kukumbukira kosasunthika, Optane DIMM, zida zothamanga kwambiri.

Vitali: Chinthu chomaliza chomwe ndikufuna kunena ndi mutu wa kafukufuku wanu wamakono: kukumbukira kosasinthasintha. Kodi tingayembekezere chiyani pankhani imeneyi posachedwapa? Mwina mumadziwa za kukhazikitsa kothandiza komwe kulipo kale? 

Michael: Sindine katswiri wa hardware, ndikudziwa zomwe ndimawerenga m'nkhani komanso zomwe anzanga amandiuza. Aliyense wamva kale kuti Intel amagulitsa Optane DIMM, yomwe ili ndi nthawi pafupifupi 3 kuwerengera latency ndi nthawi 10 kulemba latency kuposa RAM wamphamvu. Posachedwapa apezeka m'mitundu yayikulu kwambiri. Ndizoseketsa kuganiza kuti mutha kukhala ndi laputopu yokhala ndi ma terabytes angapo a RAM yolumikizidwa ndi ma byte. Ndizotheka kuti m'zaka 10 tidzasankha kugwiritsa ntchito ukadaulo watsopanowu, popeza timagwiritsa ntchito DRAM - ingowonjezera voliyumu. Koma chifukwa cha ufulu wodziyimira pawokha, mipata yatsopano imatseguka kwa ife. Titha kusintha zosungirako kuti pasakhale kulekanitsa pakati pa kukumbukira ntchito kwa byte-addressable ndi kukumbukira kosalekeza kwa block-structured. Chifukwa chake, sitidzafunika kusanja zonse zomwe zikuyenera kusamutsidwa kuchokera ku pulogalamu ina kupita ku ina kukhala mafayilo opangidwa ndi block. Kuchokera pa izi tikhoza kupeza mfundo zambiri zofunika zomwe zimakhudza machitidwe ogwiritsira ntchito, malo othamanga, ndi masitolo ogulitsa deta. Derali ndi losangalatsa kwambiri kugwira ntchito. Payekha, zimakhala zovuta kwa ine kulosera zomwe zonsezi zidzatsogolera, koma mavuto apa ndi osangalatsa kwambiri. Pakhoza kukhala kusintha kosinthika apa, ndipo amatsatira mwachibadwa kuchokera kuntchito ya multithreading, popeza kulephera kuchira ndi njira ya "multithreading" pafupi ndi ntchito yachizolowezi ya dongosolo. 

Mutu waukulu wachiwiri womwe ndikugwira nawo pano ndikuwongolera zida zothamanga kwambiri komanso mwayi wopeza zida kuchokera kumalo ogwiritsira ntchito ndi kuwongolera kwadongosolo. M'zaka zaposachedwa, pakhala pali chizolowezi chosunthira mwayi wofikira ku chipangizocho kupita kumalo ogwiritsira ntchito. Izi zimachitika chifukwa kernel stack ya TCP-IP sichitha kugwira ntchito pamwamba pa netiweki yomwe imafunikira paketi yatsopano ma microseconds 5 aliwonse; sizingachitike. Choncho, opanga amapereka mwayi wolunjika ku zipangizo. Koma izi zikutanthauza kuti opareting'i sisitimu amalephera kulamulira ndondomeko ndipo sangathe kupereka mwayi kwa chipangizo kwa opikisana ntchito. Gulu lathu lofufuza limakhulupirira kuti kuperewera kumeneku kungapewedwe. Tikhala ndi nkhani pa izi ku USENIX ATC mwezi uno. Zimakhudzana ndi kulimbikira, popeza kukumbukira kosalekeza kwa nthawi yayitali, kwenikweni, ndi chipangizo chokhala ndi I/O yothamanga kwambiri yomwe imayenera kupezeka pamalo ogwiritsira ntchito. Kafukufukuyu amapangitsa njira zatsopano zopangira ma microkernels, exokernels, ndi zoyeserera zina zachikhalidwe zosuntha magwiridwe antchito kuchokera ku OS kernel kupita kumalo ogwiritsira ntchito. 

Владимир: Kukumbukira kwa Byte ndikwabwino, koma pali kuchepa kwa thupi - kuthamanga kwa kuwala. Izi zikutanthauza kuti padzakhala kuchedwerapo mukalumikizana ndi chipangizocho. 

Michael: Zolondola ndithu.

Владимир: Kodi padzakhala mphamvu zokwanira kuti athe kupirira katundu watsopano?

Michael: Limeneli ndi funso labwino kwambiri, koma lindivuta kuliyankha. Lingaliro la kukonza kukumbukira lakhalapo kwa nthawi yayitali, ndizosangalatsa kwambiri, komanso zovuta kwambiri. Sindinagwirepo ntchito m'derali, koma zingakhale zabwino ngati zinthu zina zatulukira kumeneko. Ndikuwopa kuti ndilibenso china choti ndiwonjezere. 

Владимир: Pali vuto linanso. Zatsopano, zokulirapo kwambiri za RAM sizingafanane ndi CPU. Chifukwa chake, chifukwa cha kuchepa kwa thupi, RAM iyi iyenera kudzipatula. 

Michael: Zonse zimatengera kuchuluka kwa zolakwika pakupanga mabwalo ophatikizika. Ngati zinali zotheka kupanga zowotcha za semiconductor kwathunthu popanda chilema, ndiye kuti zingatheke kupanga microcircuit yonse. Koma tsopano sitidziwa kupanga ma microcircuits akuluakulu kuposa masitampu otumizira. 

Владимир: Koma tikukamba za kukula kwakukulu, za masentimita. Izi mosakayikira zimakhudza latency. 

Michael: Inde. Palibe chomwe mungachite ndi liwiro la kuwala. 

Владимир: Tsoka ilo. 

Chotsatira chachikulu chotsatira. Mitundu iwiri ya data. Hydra.

Vitali: Momwe ndikumvera, mumagwira zatsopano mwachangu kwambiri. Munali m'modzi mwa oyamba kugwira ntchito pokumbukira zochitika, komanso m'modzi mwa oyamba kugwira ntchito pazokumbukira zosasinthika. Kodi mukuganiza kuti chidzakhala chotani? Kapena mwina ndi chinsinsi?

Michael: Kunena zowona, sindikudziwa. Ndikukhulupirira kuti nditha kuzindikira chinthu chatsopano chikabwera. Sindinakhale ndi mwayi wodzipangira ndekha gawo latsopano, koma ndakhala ndi mwayi wochepa ndipo ndatha kuyamba kugwira ntchito molawirira m'magawo atsopano opangidwa ndi ena. Ndikukhulupirira kuti ndidzatha kuchita izi m'tsogolomu.

Алексей: Funso lomaliza muzofunsidwa likhala lokhudza momwe mumachitira ku Hydra ndi zomwe mumachita kusukulu. Ngati ndimvetsetsa bwino, lipoti la kusukulu lidzakhala lokhudza ma aligorivimu opanda kutsekereza, komanso pamsonkhano wokhudza magawo awiri a data. Kodi munganene mawu pang'ono okhudza malipoti awa?

Michael: Mwa zina, takhudzapo kale pamitu imeneyi nanu m'mafunsowa. Ndizokhudza ntchito yomwe ndidachita ndi wophunzira wanga Bill Scherer. Adalembanso ndemanga, ndipo Doug Lee adathandiziranso, ndipo pamapeto pake idakhala gawo la mizere yolumikizana ndi ulusi wambiri mu laibulale ya Java. Tiyeni tiyerekeze kuti dongosolo la deta likuwerengedwa ndi kulembedwa popanda kutsekereza, ndiko kuti, ntchito iliyonse ili ndi malangizo ochepa panjira yovuta. Ngati muyesa kuchotsa deta mu chidebe chopanda kanthu, kapena kuyesa kuchotsa deta yomwe ili mu chidebe ichi, mumadziwitsidwa mwamsanga kuti izi sizingatheke. Koma khalidwe ili silingakhale lovomerezeka ngati ulusi umafunadi deta iyi. Ndiye chinthu choyamba chimene chimabwera m'maganizo ndikupanga chipika chomwe chidzafunsa nthawi zonse ngati deta yofunikira yawonekera. Koma ndiye pali kusokonezedwa kwa wina aliyense. Kuphatikiza apo, ndi njira iyi, mutha kudikirira mphindi 10, kenako ulusi wina udzabwera, ndipo mwangozi udzalandira chidziwitso chofunikira poyamba. Ma data amitundu iwiri alibe maloko, koma amalola kuti ulusi udikire bwino. Mawu oti "kuwiri" amatanthauza kuti kapangidwe kake kamakhala ndi data kapena zopempha za data, tizitcha anti-data. Chifukwa chake ngati muyesa kutulutsa china chake m'chidebe chopanda kanthu, pempho lidzayikidwa mumtsuko m'malo mwake. Tsopano ulusi ukhoza kudikirira pempho popanda kusokoneza wina aliyense. Kuphatikiza apo, dongosolo la data limayika zofunikira pazopempha kuti zikalandiridwa, ziperekedwe kwa munthu woyenera. Chotsatira chake ndi njira yosatseka yomwe imakhalabe ndi ndondomeko yokhazikika komanso ntchito yabwino pochita. 

Алексей: Kodi mukuyembekezera chiyani kuchokera kudongosolo la datali? Kodi imathandizira pazochitika zonse zodziwika bwino, kapena ikuyenerana ndi zochitika zina? 

Michael: Ndizothandiza ngati, choyamba, mukufuna chidebe popanda kutseka, ndipo, chachiwiri, muyenera kudikirira panthawi yomwe muyenera kupeza deta kuchokera ku chidebe chomwe mulibe. Monga momwe ndikudziwira, chimango chathu chimapereka makhalidwe abwino pamene zinthu ziwirizi zakwaniritsidwa. Chifukwa chake, muzochitika izi ndikupangira kugwiritsa ntchito. Ubwino waukulu wazinthu zopanda zokhoma ndikuti amapewa zovuta zogwirira ntchito. Ndipo kudikirira ndikofunikira kwambiri mu ma aligorivimu ambiri ngati deta imasamutsidwa kuchokera ku ulusi wina kupita ku wina.

Vitali: Ndiloleni ndifotokozere: kodi mungalankhule za chinthu chomwecho kusukulu komanso pamsonkhano?

Michael: Kusukulu Ndilankhula zambiri zamitundu yambiri ya data, ndi mfundo zoyambira zomwe zafotokozedwa koyambirira kwa phunzirolo. Ndikuganiza kuti omvera akudziwa zomwe ulusi ndi wodziwa maloko. Kutengera chidziwitso choyambirirachi, ndilankhula za ma data opanda zokhoma. Ndipereka chidule cha zovuta zofunika kwambiri mderali, zokhudzana ndi mitu ngati kasamalidwe ka kukumbukira. Sindikuganiza kuti padzakhala china chovuta kwambiri kuposa mzere wa MS.

Алексей: Kodi mukukonzekera kuphunzitsa zamitundu iwiri ya data kumapeto kwa kalasi yanu kusukulu?

Michael: Ndidzawatchula, koma sindikhala nthawi yambiri pa iwo. Lipoti la Hydra lidzaperekedwa kwa iwo. Idzaphimba pulojekiti yomwe pamapeto pake idapanga Java, komanso kugwira ntchito ndi a Joe Israelevich kuti apange mitundu iwiri ya mzere wa LCRQ, ndikupanga mapangidwe apafupi ndi onse amitundu iwiri ya data.

Алексей: Chifukwa chake maphunziro kusukulu atha kulangizidwa kwa oyamba kumene, komanso maphunziro amitundu iwiri pa Hydra - kwa anthu omwe akudziwa kale?

Michael: Ndiwongolereni ngati ndikulakwitsa, koma omvera ku Hydra adzakhala osiyanasiyana, kuphatikizapo akatswiri ambiri a Java, komanso anthu ambiri omwe sakhudzidwa mwachindunji ndi mapulogalamu amitundu yambiri. 

Vitali: Inde, nzoona.

Алексей: Tikukhulupirira choncho.

Michael: Pamenepa, ndikumana ndi vuto lomwelo lomwe tidayamba nalo kuyankhulana: momwe mungapangire lipoti kukhala lolemera mokwanira muukadaulo komanso kupezeka kwa omvera onse.

Vitali: Kodi mungapereke lipoti mofanana ndi momwe mumaperekera maphunziro? Ndiko kuti, lankhulani ndi omvera ndikusintha mogwirizana ndi mmene zinthu zilili?

Michael: Ndikuwopa kuti sizingayende choncho, chifukwa lipotilo lidzakhala ndi zithunzi. Zithunzi ndi zofunika pamene omvera amalankhula zinenero zosiyanasiyana poyamba. Anthu ambiri zimawavuta kundimvetsa m’Chingelezi, makamaka ngati ndilankhula mofulumira kwambiri. Ndinasankha mitu iyi chifukwa Peter Kuznetsov adandifunsa kuti ndilankhule za ma data osatseka pasukulu ya SPTDC; kenako ndinafunikira lipoti la msonkhano wa gulu la ogwiritsa ntchito Java, ndipo ndimafuna kusankha china chake chomwe chingakhale chosangalatsa makamaka kwa opanga mapulogalamu a Java. Chophweka chinali kuyankhula za zinthu zomwe zili mu laibulale ya Java zomwe ndinali ndi dzanja mwanjira ina. 

Алексей: Tikuganiza kuti omvera pa Hydra akudziwa kale kena kake pazamasewera opanda zokhoma ndipo mwina ali ndi zina zambiri mderali. Koma izi ndi zongoganiza chabe; zinthu zidzamveka bwino pamsonkhano womwewo. Komabe, zikomo chifukwa cha nthawi yanu. Ndikukhulupirira kuti zokambiranazo zidzakhala zosangalatsa kwambiri kwa owerenga athu. Zikomo kwambiri!

Vitali: Zikomo. 

Michael: Ndidzasangalala kukumana nanu ku St. 

Алексей: Ifenso tili ndi mzinda wokongola. Kodi munayamba mwabwerako kuno?

Michael: Ayi, sindinapite ku Russia konse. Koma St. Petersburg nthaŵi zonse yakhala pa ndandanda ya malo amene sindinafikeko, koma kumene ndikufunadi kupitako, chotero ndinakondwera kwambiri ndi chiitanocho. 

Алексей: Mwa njira, tidzakhala ndi pulogalamu ya maulendo okamba nkhani. Zikomo kwambiri chifukwa choyankhulana, ndipo mukhale ndi tsiku labwino!

Mukhoza kupitiriza kukambirana ndi Michael pa msonkhano wa Hydra 2019, womwe udzachitike pa July 11-12, 2019 ku St. Adzabwera ndi lipoti "Dual data structures". Matikiti angagulidwe patsamba lovomerezeka.

Source: www.habr.com